I've got a 2300 Sq Ft Garage in which I run a detailing studio. About 1300sq ft of that will be sectioned off with a black curtain (the horizontal line in the middle of the room) part of the time, and used as a photo studio for cars and other large objects. The ceilings are 14 feet. Here's the rough floor plan for the business functions of the space:

The overall rectangle is 50x60, so the 2300sq ft doesn't include bathrooms and break room. The blue rectangles are the dimensions of a 2013 honda accord.

Now, in the evenings, the flat (which is basically a 10' by 20' frame with a white piece of spandex stretched over it, which is conveniently the material commonly used for DIY projector screens), can be dropped down against the west (left) wall. I have a BenQ w1080st on its way.

So I'd like a speaker system that can be used for the theater, and also be used for music for the studios during the day. So the theater space at 1300 sq ft, 14 foot ceilings, that's 18,200 cubic feet. That's a lot of space - even more when you consider that there's just a curtain separating that from another 14,000 cubic feet.

I'll drop the bomb right now... I'm a bit budget conscious. I know I could easily spend $10k to get this done, but that's why I'm thinking DIY - what's the best bang for the buck for filling this space with decent quality sound? The ceilings are insulation sealed in plastic, and the floors are concrete with an epoxy coating. I'll probably have some fabric along the drywall walls to help get rid of the echoing.

So what's the most efficient approach here? I would imagine using tapped horn subwoofers, but this is still fairly new territory for me.

Here's roughly what the setup would look like in the theater section:

The brown squares are chairs and the green rectangle is the ping pong table.

What's the listening distance and desired SPL? Do you like it pretty loud, or just casual background music and the occasional rom com. How much space do you have for speakers? Want to go in-wall? That setup looks like that could work, especially if you don't want big clunky speakers in the way of your work area.

What's the listening distance and desired SPL? Do you like it pretty loud, or just casual background music and the occasional rom com. How much space do you have for speakers? Want to go in-wall? That setup looks like that could work, especially if you don't want big clunky speakers in the way of your work area.

Horn subs are a good idea. Hides the woofer from being damaged too.

If there's no major downside, I'd probably hang the speakers from the ceiling actually. Keeps it off the floor, but I don't think I want to do in-wall.

As for SPL? I'd like to really impress people (including myself) with a great theater experience. It doesn't have to be insanely over-the-top audiophile quality music, but it would be nice to have pretty good range coverage for listening during the day.

It doesn't seem like that's too far off, though the thread is really hard to follow. I'm not sure if I should use what he uses and why - he doesn't go through his decision making process as much as shows "here's what I did".

All of these could be "flown" which basically means you would hang them from the upper corners angled down at the audience.

Given the sensitivity of these speakers you should be able to stick to receiver power, even in your large room. If you wanted, you could upgrade to separate amps for the front speakers.

As far as subs go, you will definitely want either a pro woofer in a large vented cabinet or some sort of a horn design. I'm not up on what the latest horn designs are. These could also be hung at the ceiling to wall junction to save floor space. Others can probably chime in with better suggestions on the subwoofer part.

That is what I would do if you want to do DIY. The other option would be to buy some good quality PA monitors like QSC K12's or KW122s. The K12's are around $850ea and are powered monitors. You could use K8s for surrounds for around $600ea.

They are similar to the kits above although not quite as refined. I'm just putting that out as an option. You would probably still want DIY subs because most pro subs only reach about 35hz.

All of these could be "flown" which basically means you would hang them from the upper corners angled down at the audience.

Given the sensitivity of these speakers you should be able to stick to receiver power, even in your large room. If you wanted, you could upgrade to separate amps for the front speakers.

As far as subs go, you will definitely want either a pro woofer in a large vented cabinet or some sort of a horn design. I'm not up on what the latest horn designs are. These could also be hung at the ceiling to wall junction to save floor space. Others can probably chime in with better suggestions on the subwoofer part.

That is what I would do if you want to do DIY. The other option would be to buy some good quality PA monitors like QSC K12's or KW122s. The K12's are around $850ea and are powered monitors. You could use K8s for surrounds for around $600ea.

They are similar to the kits above although not quite as refined. I'm just putting that out as an option. You would probably still want DIY subs because most pro subs only reach about 35hz.

Thanks for the advice! What would be an extraordinarily cost-effective way to treat the walls and ceilings?

Thanks for the advice! What would be an extraordinarily cost-effective way to treat the walls and ceilings?

That is a good question. It likely depends on how ugly or pretty you want it. The ugliest would be to crudely attach some 2" OC703 fiberglass panels to the first reflections. If you wanted the the fiberglass panels to look better you would want to wrap them in fabric. I would imagine you don't want flammable material on the walls so if you cover them in fabric that should be considered.

I'm not an acoustic treatments expert, but I think this basic approach should work well. Of course it will have to fit between whatever lighting you need for your workspace. The use of directivity controlled speakers like the ones I suggested will help to mitigate the effects of a highly reflective room, but treatments would help on top of that.

I was thinking some old carpet attached to a backing board in a convoluted fashion that could then be attached to the wall. Old carpet is dirt cheap if you get it on the curb after a heavy rain when folks rip it out of their flooded basements. And by convoluted, I mean it would look like this.

If you put a white sheet over it, or kept white sheets around your lighting for photos, it'd help keep things bright for ya.

If you put a white sheet over it, or kept white sheets around your lighting for photos, it'd help keep things bright for ya.

I do need to keep things looking nice aesthetically. Wouldn't putting a sheet over it hamper the effectiveness of the uneven surface by providing an even surface? Or will no sound bounce off of a white sheet?

By the way, I need giant stretches of white fabric anyway - anyone know of a good source of large pieces of fabric that reflect light well without spending an arm and a leg?

All but the highest frequencies will go through a thin cotton sheet. As frequencies decreases, sound absorbers must increase in thickness.

And I am no interior designer or accoustical engineer, but my idea wouldn't be to have the sheet(s) up against the wall where the sound absorbers are, but away a bit in some fashion. For example, something like this. They're not up against the ceiling and affords you the ability to hide lighting behind them, which is great for diffusion of hot spots when shooting.

I agree with Looneybomber but I wouldn't mess with old carpet. It needs to be at least 1-2" thick fiberglass or similar.

Do keep in mind that lining your walls with cotton sheets is probably a fire hazard especially if you are dealing with cars in the same space. It might be against code in your area. Either way, proceed with caution.

I agree with Looneybomber but I wouldn't mess with old carpet. It needs to be at least 1-2" thick fiberglass or similar.

Do keep in mind that lining your walls with cotton sheets is probably a fire hazard especially if you are dealing with cars in the same space. It might be against code in your area. Either way, proceed with caution.

Oh, good looking out. I forget about fire/safety codes all the time. I still burn my yard and other things despite moving into the city. Country living is so much nicer. No one cares what you do!

Oh, good looking out. I forget about fire/safety codes all the time. I still burn my yard and other things despite moving into the city. Country living is so much nicer. No one cares what you do!

Being involved with race cars for years I've seen countless fires where cars are operated indoors. Of course a detailing shop is not as volatile but it is good to be cautious about that. If something were to happen and insurance didn't cover it you could be personally liable especially if your corporate structures are not setup properly.